/*
 * Copyright 2002-2010 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

using Spring.Expressions;

namespace Spring.Caching;

/// <summary>
/// This attribute should be used to mark method that should
/// invalidate one or more cache items when invoked.
/// </summary>
/// <remarks>
/// <p>
/// This attribute allows application developers to specify that some
/// cache items should be evicted from cache when the method is invoked,
/// but it will not do any eviction by itself.
/// </p>
/// <p>
/// In order to actually evict cache items, an application developer
/// must apply a <c>Spring.Aspects.Cache.InvalidateCacheAdvice</c> to
/// all of the members that have this attribute defined.
/// </p>
/// </remarks>
/// <author>Aleksandar Seovic</author>
[AttributeUsage(AttributeTargets.Method, AllowMultiple = true, Inherited = false)]
[Serializable]
public sealed class InvalidateCacheAttribute : Attribute
{
    private string cacheName;
    private string keys;
    private IExpression keysExpression;
    private string condition;
    private IExpression conditionExpression;

    /// <summary>
    /// Creates an attribute instance.
    /// </summary>
    public InvalidateCacheAttribute()
    {
    }

    /// <summary>
    /// Creates an attribute instance.
    /// </summary>
    /// <param name="cacheName">
    /// The name of the cache to use.
    /// </param>
    public InvalidateCacheAttribute(string cacheName)
    {
        this.cacheName = cacheName;
    }

    /// <summary>
    /// Gets or sets the name of the cache to use.
    /// </summary>
    /// <value>
    /// The name of the cache to use.
    /// </value>
    public string CacheName
    {
        get { return cacheName; }
        set { cacheName = value; }
    }

    /// <summary>
    /// Gets or sets a SpEL expression that should be evaluated in order
    /// to determine the keys for the items that should be evicted.
    /// </summary>
    /// <value>
    /// An expression string that should be evaluated in order
    /// to determine the keys for the items that should be evicted.
    /// </value>
    public string Keys
    {
        get { return keys; }
        set
        {
            keys = value;
            keysExpression = Expression.Parse(value);
        }
    }

    /// <summary>
    /// Gets an expression instance that should be evaluated in order
    /// to determine the keys for the items that should be evicted.
    /// </summary>
    /// <value>
    /// An expression instance that should be evaluated in order
    /// to determine the keys for the items that should be evicted.
    /// </value>
    public IExpression KeysExpression
    {
        get { return keysExpression; }
    }

    /// <summary>
    /// Gets or sets a SpEL expression that should be evaluated in order
    /// to determine whether items should be evicted.
    /// </summary>
    /// <value>
    /// An expression string that should be evaluated in order to determine
    /// whether items should be evicted.
    /// </value>
    public string Condition
    {
        get { return condition; }
        set
        {
            condition = value;
            conditionExpression = Expression.Parse(value);
        }
    }

    /// <summary>
    /// Gets an expression instance that should be evaluated in order
    /// to determine whether items should be evicted.
    /// </summary>
    /// <value>
    /// An expression instance that should be evaluated in order to determine
    /// whether items should be evicted.
    /// </value>
    public IExpression ConditionExpression
    {
        get { return conditionExpression; }
    }
}
